How do I know if my well pressure tank is waterlogged?

A waterlogged pressure tank causes the pump to short-cycle. Test it by tapping the tank — a healthy tank sounds hollow at the top and solid at the bottom. You can also check the air valve with a tire gauge: it should read 2 PSI below your cut-in pressure. Zero means the bladder has failed.

Can I replace a pressure tank myself?

Pressure tank replacement is within reach for mechanically confident homeowners — it involves shutting off the pump, draining the system, and swapping the tank. However, it requires correctly setting the air precharge after installation. Many homeowners prefer to have a licensed contractor do it to ensure proper sizing and pressure settings.

How much does pressure tank replacement cost in 2026?

A 20-gallon bladder tank costs $250–$500 for the tank. Contractor installation typically adds $150–$300, bringing the total to $400–$800. Larger tanks or difficult access locations cost more.

What Is a Well Pressure Tank and Why Does It Matter?

August 28, 2025

Most homeowners with private wells have heard of a pressure tank but are fuzzy on what it actually does. That matters, because a failing pressure tank is the most common — and most preventable — cause of premature well pump failure.

Understanding your pressure tank takes about five minutes. That knowledge can save you thousands of dollars in pump replacement costs.

What a Pressure Tank Does

A pressure tank serves two functions: it stores a reserve of pressurized water so the pump does not have to run every time someone opens a faucet, and it maintains stable water pressure throughout your home by acting as a buffer between the pump and your plumbing.

Without a pressure tank (or with a failed one), your pump would turn on every time you opened a faucet or flushed a toilet. A pump that starts and stops dozens of times per hour instead of a few times per hour wears out in a fraction of its expected lifespan. This is called short-cycling.

How a Bladder Pressure Tank Works

Modern residential pressure tanks contain a rubber bladder that divides the tank into two chambers: one side holds water, the other holds compressed air. When the pump runs, water enters the tank and compresses the air. When a faucet opens, the compressed air pushes water out without the pump needing to run.

The pump turns on when pressure drops to the cut-in setting (usually 30 or 40 PSI) and turns off when pressure reaches the cut-out setting (usually 50 or 60 PSI). Between those pressures, the tank supplies water without the pump running.

How to Know If Your Pressure Tank Is Failing

A failing or waterlogged pressure tank shows these signs:

The pump short-cycles (kicks on and off every few seconds)
Water pressure fluctuates noticeably between pump cycles
The pressure gauge swings rapidly up and down
You can hear the pump running almost constantly
The tank sounds hollow throughout when tapped (a healthy tank should sound solid on the water side)

To test the air precharge: with the pump off and pressure bled down, check the air valve on top of the tank with a tire pressure gauge. The reading should be 2 PSI below the pump's cut-in pressure. If you get zero, the bladder has failed.

How Long Does a Pressure Tank Last?

A quality bladder-type pressure tank typically lasts 5–12 years under normal conditions. Factors that shorten tank life include high mineral content water (which accelerates bladder degradation), excessive short-cycling, and pressure settings that are set too high.

If your tank is over 7 years old and showing any of the symptoms above, replacement is usually the right call. A new 20-gallon tank runs $250–$500 for the tank plus $150–$300 for installation — a fraction of what pump replacement costs.

What Size Tank Do You Need?

Tank sizing is based on pump flow rate (GPM) and the desired pump cycle time. A general rule: a 1/2 HP pump (about 10 GPM) paired with a 20-gallon tank is adequate for most 2–3 bathroom homes. Larger homes, irrigation systems, or higher-horsepower pumps benefit from 30–50 gallon tanks.

Undersizing the tank is a common mistake on re-installations. A $50 savings on a smaller tank can cost you years of pump life. When replacing a failed tank, size up if your previous tank caused frequent short-cycling.

Does a Well Warranty Cover the Pressure Tank?

Yes — pressure tank coverage is included in the Home Well Warranty Standard and Complete plans. If your bladder fails or the tank needs replacement, the service is covered up to the plan's annual cap, and you pay only the service fee.

Because pressure tanks and pumps fail in sequence — a failed tank short-cycles the pump, which then burns out — catching the tank early is one of the most cost-effective things you can do for your system.